SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9588b8c1fb1f63d9c3ff2e3a19ccfaf53aa249b6b58fba0bb42663a6041e74d3' 
  AND token = 'Ww1J/V8HvqBMfU0cldN2YJWxx9YubM7SUV0IVcGlcxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}